DecimalDigitCount.go

/*
Given an array nums of integers, return how many of them contain an even number of digits.

Example 1:

Input: nums = [12,345,2,6,7896]
Output: 2
Explanation:
12 contains 2 digits (even number of digits).
345 contains 3 digits (odd number of digits).
2 contains 1 digit (odd number of digits).
6 contains 1 digit (odd number of digits).
7896 contains 4 digits (even number of digits).
Therefore only 12 and 7896 contain an even number of digits.
Example 2:

Input: nums = [555,901,482,1771]
Output: 1
Explanation:
Only 1771 contains an even number of digits.


Constraints:

1 <= nums.length <= 500
1 <= nums[i] <= 10^5

*/

package main

import (
	"log"
)

func main() {
	tests := [][]int{{12, 345, 2, 6, 7896}, {555, 901, 482, 1771}}
	for _, test := range tests {
		log.Printf("findNumbers(%v) == %d\n", test, findNumbers(test))
	}
}

func findNumbers(nums []int) int {
	evenDigitNums := 0
	for _, n := range nums {
		if (decimalDigitCount(n) % 2) == 0 {
			evenDigitNums++
		}
	}

	return evenDigitNums
}

// takes an integer and returns the number of decimal significant digits
func decimalDigitCount(x int) int {
	digits := []int{}
	var rem int

	for x > 0 {
		rem = x % 10
		x = x / 10
		digits = append(digits, rem)
	}

	return len(digits)
}